Constant-speed multifrequency electrical generating apparatus



W. DORNIG Nov. 4, 1930.

CONSTANT SPEED MULTIFREQUENCY ELECTRICAb GENERATING APPARATUS Filed Jan. 8, 1929 Patented Nov. 4, 1930 UNITED STATES PATENT @FFEQE WALTER DOB-NEG, F BERLIN-DAHLEM, GERMANY CONSTANT-SPEED MULTIFR-EQUENCY ELECTRICAL GENERATING APPARATUS Application filed January 8, 1929, Serial No. 331,100, and in Germany November 28, 1928.

My invention relates to a constant speed stantially equal outer diameters. Hence 2 multi-frequency electrical generating appaplus 3, or 2 plus 3 and so on, form sepratus. It is known that with the aid of difarate generators, while 4 is the common exferent transmission frequencies, a plurality citation winding. In this instance,the stators 5 of telegrams can be sent simultaneously and rotors of the separate generators or units 55 through a conducting cable, for which purare of increasing size or iron breadth as they pose, ten separate valve generators, for exare located successively further from said ample, with the frequencies 300*4:0O-500 etc. winding on both sides of the latter. The sevperiods, were employed. The use of valves is eral generators situated on each side of the Very expensive because of the necessity for excitation winding form parallel magnetic 0 repeated renewals and a machine for generpaths, and according to my invention, the reating the frequencies is therefore preferable luctances of these paths are (under maintefrom an economic standpoint. nance of the rotors of substantially the same The possibility of using a machine instead diameter) made equal by gradually increasof valves however is dependent upon the gening the iron breadths of the generators, the eration of constant frequencies and freedom more remote they are from the common excifrom oscillations from harmonics comparable tation winding. The flux moreover may be at least to that of the valves or better. brought to the optimum value by judicious Multi-frequency generators for this purselect-ion or r gulation of the air gaps be- 20 pose have been proposed in various forms, tween their stator and rotor elements, or more but the machines heretofore developed have specifically by making the air gap dimensions proved objectionable for difierent reasons, between said co-operative elements narrower and this invention provides an improved maas they are further removed from the excitachine or generating apparatus of the stated tion winding, as indicated in the drawing.

character in combination with means for As a matter of principle it is also possible,

maintaining the speed of the generators 0011- of course, to dispose all the separate generstant, ators on one side only of the excitation wind- The invention will be best understood by ing. If a very large number of frequencies description with reference to the attached be req ired, such as twenty, it becomes a mat- 30 drawings, wherein one practicable emboditer for consideration whether a single exment thereof is shown by way of example. citati n coil will suflice, and in certain cir- Tn said drawings a constructional form of cumstances, a separate source of flux may generating plant or apparatus adapted for be employed for each large group, such as ten different frequencies is shown in a someeach group for ten frequencies.

what diagrammatic manner and in part sec- Tn order to maintain a constant speed, or

tion as viewed from the side. constancy of frequency, the driving motor The illustrative generator is of the equi- 5 is controlled by any kind of device for mainpolar inductor type, wi h the particular feataining constant speed and preferably by the ture according to this invention that all the centrifugal governor 6 represented diafrequencies (i. e. the ten difierent frequen grammatically in the drawing as described, cies) are obtained from the same machine, or for example, in the Elektrotech'nische Zeitin other words, ten separate generators are schrift, 1928, llo. 47, p. 1. 13. A multi-frecombined in the same casing and receive flux quency generator constructed on the forefrom a common excitation winding" arranged going principles and operated in conjunction co-axially with the generator shaft. In this with a constant speed device gives aarticulargenerator, 1 is the casing, 2 to 2 are the ly good performance, especially as regards stators of difierent sizes but of substantially the even contour of the curves which are equal internal diameters fitted with their obtained without any mutual interference slots and windings, and 3 to 3 are the corbetween the various frequencies.

responding rotors of different sizes and sub- These multi-frequency generators are also 'eter; an excitation winding common to all of said units for providing magnetic flux therefor; means for driving said generator; and means for controlling the speed thereof;

operating rotor and stator units being decreased progressively from the units nearest the exciting winding to those'furthest from it,

thereby adapting them to independently generate different frequencies.

21A multi-frequency electrical generating apparatus, comprising a multi-frequency having a plurality of independent statorrotor generating units of substantially the same diameter combined in a single housing; an excitation winding common to the plurality'of said units for providing magnetic flux therefor; means for driving said generator, 1

and means for controlling the speed thereof,

the stator and rotor elements of the several units being of different iron breadth increasing as the units are located successively further from the excitation winding and the "air gap distances between successive cooperating rotor and stator units being progresthereby adapting them to independently generate different frequencies. r

' 3. A multi-frequency electrical generating apparatus, comprising aImulti-frequency rotor generating units of substantially the then to the plurality of said units for providing magnetic flux therefor; means fordriving said generator, and means for controlling the speed thereof, the cooperat ve stator and distance therebetween decreasing progresfrom the excitation winding, thereby adaptingthem to independently generate different frequencies at; aconstant rate with constant drive speed having a plurality of independent statorrotor units of substantially the same diamthe air gap distances between successive co- 7 generator of the homopolar inductor type} generator of the homopolar inductor'type having a plurality of independent stator' same diameter; an excitation winding comrotor elements of'the several units being of differing size or breadth and having air gap 4. A multi-frequency electrical generating apparatus, comprising a multi-frequency generator of the liomopolar inductor type havinga plurality of independent statorrotor generating units of substantially the same diameter combined in a single housing;

an excitation winding common to the plurality of said units for providing magnetic flux therefor; means for driving said generator, and means for controlling the speed thereof, the cooperative-stator and rotor elements of the several units being of successively different iron breadth increasing as the units are located further from the'excitation winding, thereby adapting them to independently generate different frequencies. I

In testimony whereof I afix my signature.

" lVALTER DORNEGQ sively decreased from the units nearest the exciting winding to those furthest from'it,

sively as they'are located successively further I 

